The objective of the proposed research is to examine the equity of access to kidney transplant waiting lists. The specific aim is to estimate the extent that biological, medical, demographic, and economic factors influence access to one or more kidney transplant waiting lists. The proposed study would be the first to study access to kidney transplant waiting lists using a nationally representative-sample of ESRD patients. It would also be the first to include adjustments for differences in patients' preferences, physicians' preferences, and quality of life on dialysis that influence the desire for transplantation and hence access to transplant waiting lists. These data will be collected via telephone interview of a cohort of 400 ESRD patients. The null hypotheses to be tested can be summarized as follows. Controlling for preferences for treatment, ESRD etiology, severity of illness, and other patient, provider, and market area factors, we test the null hypotheses that age, sex, race, and expected ability to pay no longer influence access to one or more cadaver kidney transplant waiting lists. Multivariate event history analyses will be used to address these null hypotheses. Data sources for these analyses include Medicare's ESRD Patient Management Medical Information System, the UNOS kidney transplant registry, United States Renal Data System, the National Planning Data Corporation's data base of ZIP code-level information on median income, and a specially designed survey of ESRD patients. No other studies have combined these rich data bases to estimate in such a rigorous way the determinants of access to kidney transplant waiting lists.